A multi-axis imaging system employing an array of optical imaging elements is a recent development. Related U.S. Patent Application No. 60/276,498; International Patent Application No. PCT/US02/08286; and U.S. Pat. No. 7,061,584, for example, disclose novel method and apparatus for rapidly obtaining an image of an entire slide using an array microscope. In general, this is a multiple-optical-axis, or multi-axis, imaging system having a plurality of imaging elements arranged in an array, each imaging element having one or more optical elements disposed along the optical axis of the array. Where the imaging elements are microscopes, the system is referred to as an Array Microscope (AM), or miniature microscope array (MMA) since the imaging elements are preferably very small.
In a multi-axis imaging system such as an MMA, where the imaging elements are closely packed, constructing a composite image of the entire object that is uniform and artifact-free from images formed by individual objectives remains problematic. In particular, to ensure that every region of the object is imaged, during the scanning operation of the multi-axis MMA, with at least one of the objectives of the objective array of the MMA, these objectives are arranged in a redundant spatial fashion. In particular, the objectives are placed in such a spatial pattern that results in overlapping, in the object plane, of traces across the object of at least some of the fields-of-view (FOVs) of at least some of the objectives. For the purposes of this disclosure, the FOV of an individual imaging system in an object space is defined as the projection of an image-plane sensor or a segment of an image-plane sensor (detector) associated with the individual imaging system into the object space, for example onto an object plane that is conjugate to the image plane where the image plane detector is located. As a result of the spatial overlapping, in the image plane, of the traces of at least some of the FOVs in the object plane (such overlapping caused by the process of scanning of the AM system), an initial image formed by the array of objectives includes image portions that contain images of the same object region but by different objectives.
While processing of the imaging data, received from so spatially organized objectives and judiciously chosen data normalization and/or calibration (disclosed, for example, in the U.S. patent application Ser. No. 13/803,936) enable the user to create a substantially artifact-free final composite image that is devoid of spatially overlapping portions of the image produced by different objectives, there remains a spatial limitation on how closely to one another the neighboring objective in the AM can packed caused by the size of the image. Such spatial limitation increases not only the complexity of the AM system but also increases the time needed to perform the process of imaging an object. Accordingly, in a situation where the hardware constraints impose practical limitations on the scanning operation of the AM, there remains a need to eliminate or at least reduce the amount of scanning.